Low alkalinity

[ud56]

Setting up 2 new tanks that are almost cycled. Nothing in them except rock and substrate. Mix a new batch of salt water Fritz rpm. Tested alkalinity of the new mix and it was 7.3. Did a water change in each tank and it measures 5.3. Can’t figure out what happened. I contacted Fritz but havent heard back.

 

[ndrwater]

First off, double check your test results. Simple mistakes can have a dramatic effect on test results.
That said, back in the day there was concern about Fritz salt and having additives precipitate out of solution causing a drop in Alkalinity at least.
I am NOT saying that is whats happening, but it was a rumor with some receipts many years ago...
Start with the retest first before jumping to conclusions about the salt

 

[Randy Holmes-Farley Verified Community Expert]

Cycling can lower alkalinity (the conversion of ammonia to nitrate consumes alkalinity), as can mixng new salt water and bare calcium carbonate surfaces, such as dry rock and sand.

 

[ud56]

First off, double check your test results. Simple mistakes can have a dramatic effect on test results.
That said, back in the day there was concern about Fritz salt and having additives precipitate out of solution causing a drop in Alkalinity at least.
I am NOT saying that is whats happening, but it was a rumor with some receipts many years ago...
Start with the retest first before jumping to conclusions about the salt

Did the test 3 times using Hanna checker

 

[ndrwater]

See Randy's reply above as well..

 

[ud56]

Cycling can lower alkalinity (the conversion of ammonia to nitrate consumes alkalinity), as can mixng new salt water and bare calcium carbonate surfaces, such as dry rock and sand.

0 ammonia but 5 ppm nitrite. Should I wait it out? My concern is that a new batch of salt is only giving me a dkh of 7.3 before putting it in the tank.

 

[ndrwater]

A quick google search states that Fritz RPM mixes between 8-9 DKH. 7.5 isn't that far off..
If still cycling, I wouldn't be doing water changes anyway until things have settled down with 0 Ammonia and Nitrite.
IMO you are better off being a little low than high anyway as you can always adjust UP with additional ALK additives as opposed to needing to buffer down or do water changes to drop ALK

 

[ud56]

A quick google search states that Fritz RPM mixes between 8-9 DKH. 7.5 isn't that far off..
If still cycling, I wouldn't be doing water changes anyway until things have settled down with 0 Ammonia and Nitrite.
IMO you are better off being a little low than high anyway as you can always adjust UP with additional ALK additives as opposed to needing to buffer down or do water changes to drop ALK

Do you think it will come up once nitrites hit 0? Should I switch salts? If so any recommendations? Thanks

 

[ndrwater]

Alk won't come back up after the cycle without external influence. Examples would be adding additives or a calcuum reactor (CaRx)
Any salt should be just fine regardless unless for some reason you desire to run a tank at a higher number like 10+ at which point there are salts deaigned for that.
Eg. Red Sea Blue bucket, Fritz PRO Red Line.
Personally, I would get through the cycle, keeping an eye on alkalinity while and after and adjust to your desired level using a high quality additive like BIonic Alkalinity or any other ALK additive easily found off the shelf at places like Bulk Reef Supply. You could also follow any of the recipes easily found here with a quick search if you are more of a DIY type person. Adjusting manually regardless of the additive you use will keep you engaged with your tank, but also allow you to maintain your target numbers

 

[Randy Holmes-Farley Verified Community Expert]

0 ammonia but 5 ppm nitrite. Should I wait it out? My concern is that a new batch of salt is only giving me a dkh of 7.3 before putting it in the tank.

I agree that waiting is fine, and 7.3 dKH (if accurate) in the salt mix is also fine.

 

[ColorMeGone]

Make sure your salt is well mixed up before using it. Once I get a bag of new salt I mix it up good in the bag. Could also do the same if it comes in a bucket.

 

[rtparty]

Check calcium on the new mix as well. If it’s also low, you likely have a salinity issue

 

[ud56]

Alk won't come back up after the cycle without external influence. Examples would be adding additives or a calcuum reactor (CaRx)
Any salt should be just fine regardless unless for some reason you desire to run a tank at a higher number like 10+ at which point there are salts deaigned for that.
Eg. Red Sea Blue bucket, Fritz PRO Red Line.
Personally, I would get through the cycle, keeping an eye on alkalinity while and after and adjust to your desired level using a high quality additive like BIonic Alkalinity or any other ALK additive easily found off the shelf at places like Bulk Reef Supply. You could also follow any of the recipes easily found here with a quick search if you are more of a DIY type person. Adjusting manually regardless of the additive you use will keep you engaged with your tank, but also allow you to maintain your target numbers

Make sure your salt is well mixed up before using it. Once I get a bag of new salt I mix it up good in the bag. Could also do the same if it comes in a bucket.

I will try that

 

[ud56]

Check calcium on the new mix as well. If it’s also low, you likely have a salinity issue

Haven’t checked calcium. What do you mean a salinity issue. I mix to 1.025

 

[rtparty]

Haven’t checked calcium. What do you mean a salinity issue. I mix to 1.025

If your refractometer is wrong, your salinity is wrong. All your elements are dictated by salinity. So if alkalinity and calcium are low, it signals your salinity may be low and your refractometer needs to be calibrated with Randy’s DIY solution

 

[ud56]

If your refractometer is wrong, your salinity is wrong. All your elements are dictated by salinity. So if alkalinity and calcium are low, it signals your salinity may be low and your refractometer needs to be calibrated with Randy’s DIY solution

Not using a refractometer. Using a glass hydrometer